Friction brake



FRICTION BRAKE Filed June 1l, 1931 APatented @et ii, i932` attain EARLL. BLAKE, F TACOMA, WASHINGTON AppIication led June 11,

This invention relates to a .brake of the type used on automobiles wherea band or lining is frictionally applied topa rotating drum.

The principal object of this invention is to provide a brake in whichthe band or lining is moved horizontally to engage the drum rather thanthe usual contracting or expanding operation. y

The improved form of brake involves the principle of a cone clutch whichoffers many advantages over the general type of brake. In the firstplace, less power is required to set the brake than in present types,doing away with air boosters or hydraulic devices, and giving moreclearance between the drum and the brake lining, which gives freedomfrom dragging. Positive and even tension is placed on the entire brakelining regardless of pressure applied. Periodic adjustment can also beeliminated by a constructionv which allows sufficient movement so thatthev entire brake lining may be worn out before adjust- Vment isnecessary. In this brake the entire surface is effective, allowing theentire lining to be evenly or uniformly worn out.

In the drawing Figure 1 shows a cross section of the brake lookingtoward the rear.

Figure 2 is a fragmentary view upon the line 2-2 of Figure 1.

Figure 3 is a fragmentary view upon the line 3-'3 of Figure 1. ,l

Figure 4 is a fragmentary view upon the line 4 4 of Figure 1.

As particularly shown in the accompanying drawing, an axle 1 rotates-ahub 2, said hub being secured to the axle in the usual manner by a nutO3. A disk wheel 4 is shown secured to the hub by bolts 4a and adaptedto turn therewith. A housing 5 for the rear axle carries a casting 6.which sup-ports a bearing 7 upon which the axle 1 is journaled.

The hub 2 is continued and bent inward to 4r, form adrum portion 8 whichrotates with the wheel. Secured to the casting 6 by bolts 1() is acylindrical drum9 which carries keys 11 on its outer surface. The keys11 are designed to interlock drum 9 with a spider 12 y .su which has anouter frusto-conical surface, the

Serial No. 543,715.

outside of which is adapted to interfit with the inside of the bentportion 8 of the hub 2. Secured to the outside surface of the spider 12is a lining 13 which engages the bent drum portion 8 of the hub 2,thereby forming a 55 brake. To bring the' lining and drum together, itis necessary to move the spider 12 in a horizontal direction. A spring14 is conventionally shown to provide means for normally holding thelining from contacting 30 with the drum. To A force the lining againstthe drum, rods 15 secured to the spider 12 project inward through .thecasting 6 at 16 and are pivotally fastened to bell cranks 17 which arepivotally secured to 65 brackets 18 mounted on 'casting 6.'Y A yoke 2'0connects the bell cranks to a rod 22 by pin 23, which in turn connectsto the ordinary brake operating lever.

The method of operation is as follower-mf When the car is running or thebrake otherwise released, the spider. 12 is urged to the left by meansof spring 14 and occupies the position shown in solid lines in Figures 1and Y 3, leaving ample clearance between lthe brake lining 13 and thedrum 8, as shown at 24 in Figure 1. When it is desired to set thebrakes, y the usual brake lever is operated, pulling the rod 22 in thedirection indicated by the arp rows in Figures 2 and 3. This'i'otatesthe s0 bell crank 17 to the position shown in the dotted line 24a,Figure 3, pressing rod 15 to the right, bringing the brake lining 13 onthe spider 12 into contact with the brake drum 8, consequently settingthe brake, asvshown 35 in dotted lines 25, Figure 1: By proportioningthe parts so -that considerable ace is provided between the hub 2 andthe splder 12,

itl will be seen that the entire brake lining l maybe worn away beforethe spider 12 comes 920 I in Contact with hub 2.' Upon releasingthe rod22, the spider '12,' with the brake lining 13, is forced away from thebrake drum 8, which releases the brake. The spider 12, having norotating action relative to castin 6, will naturally cause a friction ordrag w en coming in contact with the brake drum 8, which is rotatingwith the wheel.

I claim v A brake for vehicles including an. axle housing, an axletherein, a Wheel mounted on the axle, a braking drum carried by theWheel and having a braking surface inclined to the axis of the drum, asupporting drum carried by the axle housing, a spider keyed on thesupporting drum for axial movement with respect thereto, the spiderhaving a braking surface for cooperation With the braking surface of thedrum, a pair of rods projecting from the spider and through the housing,bell crank levers pivoted on the outside of the housing, one arm of eachof the bell crank levers engaging the outer ends of the rods, a yokepivoted to the free ends of the other arms of the bell crank levers, anoperating rod pivoted to the yoke to actuate theJ bell crank levers andforce the brakingA surfaces into contact, and a spring interposedbetween the spider and the braking Wheel to normally disengage thebraking surfaces.

In testimony whereof I afIiX my signature.

. EARL L. BLAKE.

